This invention is directed to a microwave oven with a timer device for selecting and/or indicating a cooking time, said oven comprising a microwave source fed by a power supply in which the mains voltage is transformed to a rectified high voltage which is supplied to the microwave source, a ripple voltage related to the mains frequency appearing in said power supply during generation of microwave energy by the microwave source.
According to the prior art, said timer device is usually controlled via a control unit included in said microwave oven. The main purpose of said control unit is to control and supervise the cooking procedure in the oven by controlling the microwave energy which is fed to the oven cavity depending on selected control parameters for the actual food. This kind of control of the timer device is used, among others, in Philips microwave oven type AVM 730. A control unit of this type means that a number of active switching components, e.g. transistors, are used in the control circuit of the timer device. In said Philips microwave oven a TRIAC performs the connection of a motor included in the timer device to the mains-AC-voltage when the oven is started. The use of active components means higher costs and moreover an increased complexity of said control unit.